鉄筋コンクリート構造物の耐震安全性について (2) : 主として, 中低層, 純ラーメン構造を対象として

Abstract

In this paper the aseismic safety of medium or low rise reinforced concrete rigid frames without shear walls is investigated on the basis that the steady-state resonance of such a frame as subjected to the sinusoidal forces at the foundation is able to be considered as the critical state. The criteria of the aseismic safety are given by applying the elasto-plastic hysteresis loops and fatigue characteristics of reinforced concrete members to such a critical state. Consequently the allowable maximum acceleration amplitude of the forced ground vibration is expressed as the function of the ductility factor (μ) and the factor F(s) which is related to the shape of the hysteresis loops (cf. Eqs. 17, 17', 17"). Numerical examples on the aseismic safety of one-story and four-story real reinforced concrete structures are presented. From these examples it is able to be concluded that the necessary minimum base shear force coefficient of the ordinary types of medium or low rise reinforced concrete rigid frames is about 0.6.